Fecal microbiota transplantation (FMT) is an effective treatment for recurrent Clostridium difficile infection (rCDI). Few studies have evaluated clinical factors associated with microbial engraftment. We describe microbial changes post-FMT and clinical factors impacting engraftment.
Patients undergoing FMT for rCDI via colonoscopy were enrolled. Clinical data and stool were collected pre- and 8 weeks post-FMT. Microbial profiles were assessed by 16S rRNA sequencing. Difference in microbial alpha and beta-diversity between groups was determined. Significance testing was assessed using Mann-Whitney-Wilcoxon and PERMANOVA tests. The Jensen Shannon Divergence (JSD) between donor and their recipient post-FMT was used as a measure of engraftment. The association of clinical factors on engraftment was evaluated by linear regression.
A total of 12 patients received an FMT from 12 unique donors. The efficacy rate was 92%. Mean recipient age was 60 years (range: 33-87) with more females (7/12).
Recipients pre-FMT alpha diversity was significantly lower compare to donors (p=0.04, Fig 1a). This difference dissipated post-FMT (p=0.67). On beta-diversity analysis, the recipients pre-FMT samples clustered separately from their post-FMT samples (p=0.01, Fig 1b), with the post-FMT samples shifting closer to the donor samples. Proteobacteria was dominant in patients’ pre-FMT samples and were substantially reduced post-FMT, combined with an expansion in Bacteroidetes (Fig. 2).
On linear regression analysis, clinical factors (age, sex, previous recurrent CDI episodes, inflammatory bowel disease, proton pump inhibitor, immunosuppression, previous anti-CDI antibiotic courses, probiotics) were not significantly associated with engraftment outcomes.
There is a significant and durable shift in recipients’ microbial profile to resemble their donor post-FMT. Recipients’ pre-FMT clinical factors did not significantly affect microbial engraftment. Future metagenomic studies may help elucidate whether clinical factors impact engraftment.
Fig 1A: Alpha diversity
Fig 1B: Bray-Curtis Principle component plot
Fig 2: Relative abundance of taxa at Phylum level
P. Panchal, None
E. Shu, None
M. Carrellas, None
Z. Kassam, None
J. Allegretti, None